There was a surge of interest in participating in the Battery500 initiative. When we at DOE said $2 million per year, that was a minimum. There was a lot of interest, and we received a lot of good applications. We found extra money to fund more than we anticipated, including money from the US Army.

— David Howell, Deputy Director, Vehicle Technologies Office, Office of Energy Efficiency & Renewable Energy, US DOE

DOE opted for 18 months for the Phase 1 effort to give the projects enough time to show proof of principle in the proposed technologies, Howell said. For such high-risk projects, 12 months is difficult, and, “we didn’t want to wait two years.”

Source: DOE 2017 Merit Review. Click to enlarge.

The Battery500 project is focused on three keystone projects:

• A high nickel content cathode with a Li-metal anode;

• Sulfur cathode and Li-metal anode; and

• Innovative electrode and cell design.

The Seedling projects are intended to enhance one of the three keystone projects, or to provide new concepts.

We have projects in both areas. Some of the seedlings fill the gaps in expertise, and then some applications propose unique designs. We are very excited about the Seedling applications we have—they fill a lot of the gaps.

If we are going to meet the 500 Wh/kg mark at the cell level, we have to work on a good cathode, put it together with a good electrolyte, maybe solid state, and the anode, all in a unique architecture.

—David Howell

Howell said the Battery500 keystone projects themselves are well underway, with full participation in the annual Merit Review planned for next year.

• Nickel-rich cathodes today (NMC) have somewhere around 30-40% nickel in the cathode itself. To achieve higher energy density goals, Howell said, you need more nickel. However, that can blowback on cycle life. Howell said that some of the researchers are seeing a 30-40% increase in capacity through using a different binder technology in conjunction with a Li-metal system. He expects a first baseline cell by the end of the first fiscal year and a test by the end of the calendar year.

• Sulfur coupled with Li metal has the highest energy density outside of Li air systems, Howell said. While there are still huge gains to be made even falling short of the theoretical capacity of the system, there are also significant problems, he noted. Dendrite growth with a Li metal anode can short out the cell within 10-30 cycles. There are a lot of good ideas on how to mitigate those issues, Howell said—but it will take time.

We have made a lot of progress in the past in Li-ion technology. We are taking the expertise and refocusing it on the longer term issues. If we can achieve our targets, that would result in a significant boost in the performance of batteries and a significant reduction in cost.

—David Howell

The new seedling projects were announced 12 July as part of a larger unveiling of a total of $19.4 million in new DOE funding for vehicle technologies research.